==================================================================
BUG: KASAN: null-ptr-deref in memset include/linux/string.h:333 [inline]
BUG: KASAN: null-ptr-deref in choke_reset+0x208/0x340 net/sched/sch_choke.c:330
Write of size 8 at addr 0000000000000000 by task syz-executor.1/26355

CPU: 1 PID: 26355 Comm: syz-executor.1 Not tainted 4.19.121-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 kasan_report_error mm/kasan/report.c:352 [inline]
 kasan_report mm/kasan/report.c:412 [inline]
 kasan_report.cold+0x194/0x2b9 mm/kasan/report.c:396
 memset+0x20/0x40 mm/kasan/kasan.c:285
 memset include/linux/string.h:333 [inline]
 choke_reset+0x208/0x340 net/sched/sch_choke.c:330
 qdisc_reset+0x6b/0x4c0 net/sched/sch_generic.c:933
 dev_deactivate_queue.constprop.0+0x138/0x220 net/sched/sch_generic.c:1132
 netdev_for_each_tx_queue include/linux/netdevice.h:2107 [inline]
 dev_deactivate_many+0xe2/0xb30 net/sched/sch_generic.c:1189
 __dev_close_many+0x128/0x2e0 net/core/dev.c:1476
 __dev_close net/core/dev.c:1501 [inline]
 __dev_change_flags+0x253/0x620 net/core/dev.c:7664
 dev_change_flags+0x7e/0x140 net/core/dev.c:7735
 dev_ifsioc+0x286/0x8d0 net/core/dev_ioctl.c:237
 dev_ioctl+0x1ab/0xc58 net/core/dev_ioctl.c:488
 sock_do_ioctl+0x1b7/0x2f0 net/socket.c:973
overlayfs: failed to resolve './file': -2
 sock_ioctl+0x325/0x610 net/socket.c:1074
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xcda/0x12e0 fs/ioctl.c:688
 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705
 __do_sys_ioctl fs/ioctl.c:712 [inline]
 __se_sys_ioctl fs/ioctl.c:710 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c829
Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f4df31c8c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004f2de0 RCX: 000000000045c829
RDX: 0000000020000000 RSI: 0000000000008914 RDI: 0000000000000008
RBP: 000000000078bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000688 R14: 00000000004c9601 R15: 00007f4df31c96d4
==================================================================